Duplex centrifugal pump.



R. K. JACK.

DUPLEX, CENTRIFUGAL PUMP.

APPLICATION FILED Aue.a,191a

ygyg Patented June 12, 1917.

2 SHEETS-SHEET I.

{NVENTOR ATTORNEYS R. K. JACK. DUPLEX CENTRIFUGAL PUMP.

APPLICATION FILED AUG.8, 1916.

Patented June 12, 1917.

2 SHEETS-SHEET 2.

WITNESSES: @a/wf nomini: n. JACK, or NUTLEY, NEW JERSEY.

'DUPLEX CENTRIFUGAL PUMP.

Specification of Letters Patent.

Patented June i2, i917.

Application filed August S, 1916. Serial No. 113,688.

To all 'whom t may concern:

Be it known that I, ROBERT K. JACK, a subject of the King of GreatBritain, residing at Nutley, in the county of Essex and State of NewJersey, have invented certain new and useful Improvements in DuplexCentrifugal Pumps; and l do hereby declare the following to be a full,clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame, reference being had to the accompanying drawings, and tocharacters of reference marked there,- on, which form a part of thisspecification.

The present invention relates, generally, to improvements in fiuidpumps; and the invention has reference, more particularly, to a novelconstruction of centrifugal pump.

The present invention has for its principal object to provide a verysimple, compact. and eiiicient construction of duplex centrifugal pumpwhich will provide for the discharge of two streams under the impellingforce of a rotary impeller.

A further object of the present invention is to provide a novelconstruction and arrangement of duplex centrifugal pump which isparticularly adapted for use in maintaining circulation in the coolingsystems of the modern V-shaped miilti-cylinder gas-engine, now employedso extensivelyv as the power plant of autovehicles, aeroplanes, etc. lnsuch V-shaped multi-cylinder gas-engines, the cylinders are angularlydisposed in two sets upon opposite sides of the crank-shaft thereof;consequently it is found to be the better and moreefficient practice todivide the circulation of the cooling medium serving such cylinders,which is obtained from a suitable radiator reservoir, into twoseparately circulating streams, one for each set of cylinders. Mypresent invention, therefore, provides a very simple and compactconstruction of duplex centrifugal pump, which, through the rotation ofa single driving-shaft and the impeller afiixed thereon, is adapted tocontrol and force the circulation of two separate and distinct streamsof cooling medium, with a minimum expenditure of power. Said novelduplex centrifugal pump will furthermore provide a proper equal iiowefficiency to each stream, so that each set of engine cylinders receivesits proper and necessary share of cooling medium from the radiatorconstituting the source thereof.

A still further object of the present invention is to provide a duplexcentrifugal pump so constructed and arranged that the impeller issubjected botli to an axial balanced pressure and a Ibalanced pressureat right angles to its axis during operation7 consequently reducing sidethrust, and the friction induced thereby,` so that economy of drivingpower, and a more efficient utilization of said driving power isobtained.

@ther objects of the present invention, not at this time moreparticularly enumerated, will be clearly understood from -tlie followingdetailed description of the same.V

With vthe various objects of the present invention inview, the sameconsists, primarily, in the novel construction of duplex lcentrifugalpump hereinafter set forth; and

the invention consists, furthermore, in the novel arrangements andcombinations of the various devices and parts, as well as in the detailsof the construction of the said parts, all of which will be more fullydescribed in the following specification, and then finally embodied inthe claims which are appended to and which form an essential part of thesaid specification.

The .invention is clearly illustrated in the accompanying drawings, inwhich:-

Figure l is a side elevation lor face view of the novel construction ofduplex centrifugal pump, made according to and embodying theprinciples'of my present invention.

Fig. 2 is a top edge or plan view of the saine.

Fig. 3 is a horizontal section of the same, taken on line 33 in saidFig. l, looking downward.

Fig. 4 is a vertical cross section of the same on line 4-4-4 in saidFig. 3, looking in the direction of the arrow a'.

Fig. 5 is a side elevation of the novel construction of impeller,forming a part of my duplex centrifugal pump, the same being removedfrom the latter; and Fig. 6 is an edge view or elevation of the same.

Similar characters of reference are einployed in all of the hereinabovedescribed views, to indicate corresponding parts.

Referring now to the said drawings, the reference character l indicatesa complete duplex centrifugal pump, made according to and embodying theprinciples of my presbase or bracket 3. Said main body or casing 2provides a centrally disposed chamber 4, in which the movable element ofthe pump, comprising a rotary impeller 5, is mounted. Located so as toextend around said chamber 4 are a pair of annular chambers a and b,which are divided or separated, one from the other, by a centrallydisposed annular partition or wall 6. Said chambers a and b communicatewith the impeller 5 by means of annular openings or passages 7 whichextend around the periphery of said impeller 5. The annular chamber a isspirally enlarged from its point of beginning until it terminates in adischarge pipe 8, which extends toward the left hand at the upper sideof the casing 2, and the annular chamber b' is spirally enlarged fromthe point of its beginning until it terminates in a discharge pipe 9,which extends toward the right hand, at the lower side of the vcasing'2.As thus disposed and arranged it will be noted that both annularchambers a and b extend spirally in the same annular direction, but thatthe point of beginning of the one is y diametrically opposite the pointof beginning of the other, and that the discharge point of the one isdiametrically opposite the discharge point of the other. The centrallyVdisposed chamber. 4 .is preferably closed on one side by a side-wall 10,from which said baseor bracket 3 preferably extends, while the oppositeside of said chamber 4 is provided with an internally screw threadedopening 11, in which is screwed an externally threaded cover-plate 12,which thus serves to normally close said chamber 4, but also permits,when removed, access to said chamber 4 for the insertion therein, orremoval therefrom, of said impeller 5.

Formed in said side-wall r10 is a centrally disposed opening or intakeport 13, communicating with one.v side of said lchamber 4. Formedpreferably as an Aintegral part of said side-wall 10, so as to terminateat and communicate with said opening or intake port 13, is an intake 'orsuction .pipe 14, extending transversely and outwardly therefrom.- Inlike manner. formed in said coverplate 12 is a centrally disposedopening or intake port 15, communicating with the opposite side ofsaid'chamber 4. Formed preferably as an integral part of said coverplate12, so as to terminate. at-and communicate with said opening or intakeport 15, is an intake or suction pipe 16, extending transverselyoutwardly therefrom.

Integrally formed in the outer wal'l of said intake or suction pipe 14is a gland 17, the outer end of which isthreaded to receive astuffing-box 18. Mounted in said gland 17 is a bearing bushing or seat19. In

within which is mounted a'bearing bushing or seat 21. Journaled vinsaid'arespective bearing bushings or seats- 19 and 21 is a' drivingshaft 22. A suitable packing 23 is retained about said shaft where thesame enters the bushing or seat 19 by the stuffing box 18, thuspreventing leakage through the shaft-bearing. Said impeller 5 is fixedupon and driven by said shaft 22. Of course it will be understood that,if it is desired to extend said driving shaft 22 through saidcover-plate 12, a gland and stuiing-box may be'substituted for saidsocket or thrust bearing-member 20.

trally disposed portion or wallY 26 spaced between its opposite outerside walls 27, so as to provide two sets of impeller passages a and b.The impeller passages a communicate, at their discharge ends located atthe periphery of theimpeller, with the annular opening or passage `7leading into said annular chamber a; and the impeller passages bcommunicate, at their discharge ends, with the annular opening orpassage 7 leading into said annular chamber 72. Each side wall 27 ofsaid impeller 5 is provided with a centrally disposed receiving orentrance port 28, which respectively communicate with said intakey port13 on the one side of said chamber 4 and theintake port 15 onI the otherside of said chamber 4. The impeller passages a and b lare formed by aseries of 'radially disposed curved impeller vanes or zreceived into theimpeller through its centrallyldisposed entrance ports 28 on each sidethereof. It therefore follows that the pressure of each stream, thusentering the impeller upon opposite sides thereof, is balanced one bythe other since the pressure of the iow of one, tending to .move theimpeller axially in one direction, is counteracted by the pressure .oflthe oppositely directed vii'ow of the other, tending to move theimpeller axially i-n an .opposite direction; consequently the impellerwhen rotated is sub-- jected to an axial balanced pressure greatlyreducing side thrust or play and consequent increased friction by reasonof such thrust against the bearing surfaces or seats 24 and 25. Eachstream of fluid thus entering the interior of the impellei` ismaintained sep'- arate from the other by said middle partition or wall26. Consequently .the two streams of Huid entering the impeller areseparately set in motion by the impeller vanes or blades 29 whichcontacting therewith set up the whirling or centrifugal action tendingto forcefully eject the same therefrom and through the annular passages7 respectively into the annular chambers a and Z7, the whirling forcecarrying the streams of fluid through said annular chambers a and b sothat the same are forcibly discharged through the respective dischargepipes 8 and 9 with considerable velocity. It will be understood thatsince the passages a and are spirally enlarged from `their points ofbeginning toward their discharge points at the discharge pipes 8 and 9,the cross sectional areas thereof are constantly increasing toward suchdischarge points, and therefore the flow of the fluid displaced. ordischarged about the entire periphery of the impeller is not choked orchecked since the capacity of each chamber a and b is proportionallyincreased with the volume of discharge toward the exit through thedischarge pipes 8 and 9. An additional novel feature in the constructionand relation of the chambers a and b, is found in their respectivedisposition or position relative to one another, whereby the points oftheir begining and discharge are diametrically opposite each other. Suchdisposition thereof tends to balance the pressure or reaction at theperiphery of the impeller, and in lines at right angles to the axisthereof, since any pressure or reaction due to the discharge of thefluid at any particular point of the impeller is balanced by exactly thesame pressure or reaction diametrically opposite, since the combinedcross sectional area of the chambers a and b at one point of discharge from the impeller is exactly the same as the y combined cross sectionalarea of the said chambers a and b at a point of discharge from theimpeller diametrically opposite thereto. By thus constructing the pumpso as to eliminate unbalanced pressure upon itsimpeller either in thedirection of its axis or at right angles thereto. it will be clearlyevident that a very smooth and easy operation of the impeller isattained with a minimum degree of friction, and with a consequenteconomical conservation of driving power in proportion to the workaccomplished by the ump.

A still further novel feature of construction embodied in my novel pump,which makes for beneficial results in the operation sage,

thereof, comprises the construction of the impeller 5 wherein theoutside Walls 27 are provided. These Walls, in conjunction with thecentral wall 26 provide inclosures over the impeller' vanes or blades 28whereby the impeller passages a and b are provided, thus providing anunobstructed free pasmoving with the stream of fluid impelled thereby,so that the mass of fluid does not have to be moved against a stationarysurface with consequent friction, and tendency to cause impeding eddiestherein which interfere with the free Centrifugal movement of the fluid.By reason of this novel construction the efficiency of the pump isincreased, and a more efficient consumption of the power applied theretofor the operation thereof is attained.

-I am aware that some changes may be made in the several arrangementsand combinations of the various devices and parts of my presentinvention, as well as in the details of the construction of the same,without departing from the scope of the said invention as set forth inthe foregoing specification, and as defined in the claims appendedthereto. Hence, I do'not limit my invention to the exact arrangementsand combinations of the Various parts as described in the foregoingspecification, nor do "l confine myself to the exact details of theconstruction of the said parts as illustrated in the accompanyingdrawings.d

1. In a device of the kind described, a casing provided with a pair ofannular chambers spirally enlarged from their points of beginning towardtheir points of discharge, annular passages formed at the juncture ofsaid annular chambers with the main body of said casing, the point oflbe.- ginning and point of discharge of one of said annular chambersbeing respectively diametrically opposite the point of beginning andpoint of discharge of the other annular chamber, a rotary impellermounted Within said casing adapted to discharge Huid through saidannular passages into said respective annular chambers to forcibly ejectsaid fluid from the latter at their discharge points, and means fordelivering fluid to said impeller.

2. In a device of the kind described, a casing provided with a pair' ofannular chambers spirally enlarged from their points of beginning towardtheir points of discharge, annular passages formed at the juncture ofsaid annular chambers with the main body of said casing, the point ofbeginning and point of discharge of one of said annular chambers beingrespectively diametrically opposite the point of beginning and point ofdischarge of the other annular chamber, said casing being provided inits sides with intake ports, intake or suction pipes connected with saidcasing so as to communicate with said intake ports, and a rotaryimpeller having radially disposed curved impeller vanes mounted withinsaid casing in communication with said intake ports, said impeller beingadapted to discharge the fluid received through said` intake portsperipherally through said annular passages into said respective annularchambers to forcibly eject said fluid from the latter at their dischargepoints.

3. In a device of the kind described, a casingprovided with a pair ofannular chambers lspirally enlarged 'from their points of beginningtoward their points of discharge, annular passages formed at thejuncture of said annular chambers with the main body of said casing, thepoint of beginning'and point of discharge of one of said annularchambers being respectively diametrically opposite the point ofbeginning and point of discharge of the other annular chamber, saidcaslng being provided in its `sides with intake ports, intake or suctionpipes connected with said casing so as to communicate with said intakeports, a rotary impeller having side walls, a central Wall dividing theinterior of said impeller transversely of its axis to form Vtwo interiorchambers open at the periphery of said impeller respectivelyto...communi cate with said respective annular passages leading to saidannular chambers of said casing,`radially disposed curved' impeller'vanes extending through eacli interior chamber of said impeller,l andthe sidewalls of said impeller having centrally disposed entrance portscommunicating respectively with said intake portsof said casing.

4. In a device of the kind described, a casing providing a centrallydisposed chamber, a fixed wall of said casing inclosingone side ofvlsaidlcentral chamber, a removable cover-portion closing the other sideof said central chamber, said* casing being provided with a pair of,annular chambers spirally enlarged from Atheir pointsiof beginningtoward their-points of discharge, discharge pipes connected withsaid'casing and extending outwardly from the respective points ofdischarge of said annular chambers, said casing, being fur-` therprovided with .a pair of annular pas-l sages aiiordingcommunication,between said central chamber and said respective annularchambers, the point of beginning, and point of discharge of one annularchamber being respectively diametrically opposite the point of beginningand point of discharge of the other annular chamber, a lrotary impellermounted within said central @chamber of said casing adaptedA todischarge fluid through said annular assages into` said respectiveannular cham ers to forcibly eject said fluidA through said dischargepipes, a

driving shaft for operating said impeller,

' means connected with said casing and its cover-portion for journalingsaid shaft, and means for delivering fluid to said impeller.

5. In a device of the kind described, a casing providing a centrallydisposed chamber, a fixed wall of said casing'inclosing one side of saidcentral chamber, a removable cover-portion closing the other side ofsaid central chamber, said casing being provided with a pair of annularchambers spirally'enlarged from their points ofbeginning to ward theirpoints of discharge, discharge pipes connected with said casing andextending outwardly from the respective points of discharge of saidannular chambers, said casing being further provided with a pair ofannular passages affording communica-- tion between said central chamberand said respective annular chambers, the point of beginning and pointof discharge of one annular chamber being respectively diametricallyopposite the point of beginning and point of discharge of the otherannular chamber, said casing being provided respectively in its sidewall and cover-portion with centrally disposed intake ports, intake or.

suction pipes connected respectively with said casing and itscover-portion so as to communicate w1th sald intake ports, a rotary jimpeller mounted within saidv central cham-A ber of said casing, thesame having radially disposed curved impeller vanes, said impeller beingadapted to discharge the fluid portion closing the other side of saidcentral chamber, said casing being provided with a pair of] annularchambers spirally enlarged from their points of beginning toward theirpoints of discharge, discharge pipes connected with said casing andextendlnfgoutwardly from the respective points of ischarge of saidannular chambers, i said casing being further provided with a pair ofannular passages ailording communication between said centralChamberland said respective annular chambers, the 4point of beginningand point of discharge' of. one annular chamber being respectivelydiametrically opposite the point of beginningandvpoint .of `discharge ofthe other annular chamber, said casing being provided respectively inits side Wall and cover-portion with centrallydisposed intake ports,intake or suctionl pi'p'esconnected respectively With said casing andits coverportion so as to communicate With said intake ports, a rotaryimpeller having side walls, a central Wall dividing the interior of saidiinpeller transversely of its axis to, form two interior chambers openat the periphery of said impeller respectively to communication withsaid respective annular passages leading to said annular chambers ofsaid casing, radially disposed curved impeller vanes extending througheach interior chamber of said impeller, said side Walls of said impellerhaving centrally disposed entrance ports communicating respectively withsaid intake ports, a driving shaftV for 15 set forth above I havehereunto set my hand 20 this 3rd day of August, 1916.

ROBERT K. JACK.

Witnesses:

GEORGE D. RICHARDS, FREDK H. W. FRAENTZEL.

